"[T]he Teamsters fund was hurt badly by the steep market decline of 2008. Those overseeing the fund also tie its troubles to the decline of unionized employment in the trucking industry, which has translated into fewer contributions to the plan.... But an examination of the fund identified other pernicious forces: most notably, illiquid, opaque and high-cost investments. At least 40 percent of the fund is in so-called alternative investments, including expensive private equity deals, hedge funds and real estate. For a fund poised to suspend benefits, holdings like these are especially problematic."